I'm making an inventory system from This YouTube Video and I can't seem to get it to work.

the error1: Assets\Scripts\InventoryScripts\InventorySystem.cs(31,33): error CS1579: foreach statement cannot operate on variables of type 'InventorySlot' because 'InventorySlot' does not contain a public instance or extension definition for 'GetEnumerator'

The error2:

Assets\Scripts\InventoryScripts\InventorySystem.cs(55,19): error CS0029: Cannot implicitly convert type 'System.Collections.Generic.List' to 'InventorySlot'

And my code:

using System.Collections;
using System.Collections.Generic;
using System.Linq;
using UnityEngine;
using UnityEngine.Events;

[System.Serializable]
public class InventorySystem
{
    [SerializeField] private List<InventorySlot> inventorySlots;

    public int InventorySize => InventorySlots.Count;
    public List<InventorySlot> InventorySlots => inventorySlots;

    public UnityAction<InventorySlot> OnInventorySlotChanged;

    public InventorySystem(int size)
    {
        inventorySlots = new List<InventorySlot>(size);

        for(int i = 0; i < size; i  ) 
        {
            inventorySlots.Add(new InventorySlot());
        }
    }

    public bool AddToInventory(InventoryItemData itemToAdd, int amountToAdd)
    {
        if(ContainsItem(itemToAdd, out InventorySlot invSlot))
        {
            foreach(var slot in invSlot) 
            {
                if(slot.RoomLeftInStack(amountToAdd))
                {
                    slot.AddToStack(amountToAdd);
                    OnInventorySlotChanged?.Invoke(invSlot);
                    return true;
                }
            }
        }

        if(HasFreeSlot(out InventorySlot freeSlot))
        {
            freeSlot.UpdateInvSlot(itemToAdd, amountToAdd);
            OnInventorySlotChanged?.Invoke(freeSlot);
            return true;
        }
        
        return false;
    }

    public bool ContainsItem(InventoryItemData itemToAdd, out InventorySlot invSlot)
    {
        invSlot = InventorySlots.Where(i => i.ItemData == itemToAdd).ToList();
        return invSlot == null ? false : true;
    }

    public bool HasFreeSlot(out InventorySlot freeSlot)
    {
        freeSlot = InventorySlots.FirstOrDefault(i => i.ItemData == null);
        return freeSlot == null ? false : true;
    }
}

I'm just trying to remove these errors so I can test it.

CodePudding user response：

The Where method of the List class returns a List rather than a single InventorySlot object.

You can rewrite the function 'ContainsItem' like this:

public bool ContainsItem(InventoryItemData itemToAdd, out InventorySlot invSlot)
{
    invSlot = InventorySlots.FirstOrDefault(i => i.ItemData == itemToAdd);
    return invSlot == null ? false : true;
}